GEOLOGY

Detailed explanation-1: -Upwelling is a process in which deep, cold water rises toward the surface. This graphic shows how displaced surface waters are replaced by cold, nutrient-rich water that “wells up” from below. Conditions are optimal for upwelling along the coast when winds blow along the shore.

Detailed explanation-2: -Winds blowing across the ocean surface often push water away from an area. When this occurs, water rises up from beneath the surface to replace the diverging surface water. This process is known as upwelling.

Detailed explanation-3: -Effects of Upwelling Because the deep water brought to the surface is often rich in nutrients, coastal upwelling supports the growth of seaweed and plankton. These, in turn, provide food for fish, marine mammals, and birds. Upwelling generates some of the world’s most fertile ecosystems.

Detailed explanation-4: -Upwelling is most common along the west coast of continents (eastern sides of ocean basins). In the Northern Hemisphere, upwelling occurs along west coasts (e.g., coasts of California, Northwest Africa) when winds blow from the north (causing Ekman transport of surface water away from the shore).

Detailed explanation-5: -Upwelling does not just happen anywhere but in certain regions of wind-sea interaction. Along the west coasts of continents in the northern hemisphere northerly winds (coming from the north) are responsible for this phenomenon while in the southern hemisphere southerly winds cause upwelling.